Answer:
The correct answer is = p = 15 and q = 6.
Step-by-step explanation:
Given:
Perimeter of rectangle = 42 cm
p - q = 9 cm
length = p
width = q
we know:
Perimeter of rectangle= 2(l+w)
solution:
42 = 2(P+q)
21= p+q
Difference of p and q = 9 cm.
Then, P+q=21 .... 1
P-q=9 ....2
Adding both 1 and 2
2P = 30
P= 15cm and
q = 15-9
= 6cm
Answer:
C
The line is from -3 to 3 and the circles are closed
Given function is a direct variation
Step-by-step explanation:
The direct proportion is defined as the increase in one quantity causes increase in other quantity.
If y is directly proportional to x, then it is given as:
y = kx
where k is the constant of proportionality
Given
y = 3x
Comparing the general form and given equation we see that both are same where k =3
So,
Given function is a direct variation
Keywords: Variation, functions
Learn more about functions at:
#LearnwithBrainly
Answers:
- Total equation: x+y = 80
- Legs equation: 2x+4y = 248
- How many ducks? 36
- How many cows? 44
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Further explanation:
- x = number of ducks
- y = number of cows
x+y = 80 is the total equation (ie the head count equation) since we assume each animal has 1 head, and there are 80 heads total.
That equation can be solved to y = 80-x after subtracting x from both sides.
The legs equation is 2x+4y = 248 because...
- 2x = number of legs from all the ducks only
- 4y = number of legs from all the cows only
- 2x+4y = total number of legs from both types of animals combined
We're told there are 248 legs overall, so that's how we ended up with 2x+4y = 248
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Let's plug y = 80-x into the second equation and solve for x.
2x+4y = 248
2x+4( y ) = 248
2x+4( 80-x ) = 248
2x+320-4x = 248
-2x+320 = 248
-2x = 248-320
-2x = -72
x = -72/(-2)
x = 36
There are 36 ducks
Now use this x value to find y
y = 80-x
y = 80-36
y = 44
There are 44 cows.
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Check:
36 ducks + 44 cows = 80 animals total
36*2 + 44*4 = 72 + 176 = 248 legs total
The answers are confirmed.
